Cardiac Risk Assessment in Kidney Transplant Candidates: Clinical Usefulness of Different Guidelines.

Although cardiovascular (CV) assessment is recommended to minimize perioperative risk in all potential kidney transplant recipients, the utility and reliability of various assessment methods are not well established. In this study, we investigated the CV evaluations and outcomes of standardized CV assessment protocols (Lisbon and American Society of Transplantation [AST]) in potential kidney transplant recipients. Data were analyzed for 266 end-stage renal disease patients (mean age 45.4 ± 13 years, female-to-male ratio 126:140) accepted for kidney transplantation wait-listing. Patients were classified as low and high cardiac risk according to their first cardiac evaluation. Major cardiovascular events (CVEs) and deaths were recorded. At the end of follow-up (median 639 days), 72 (27.1%) patients underwent kidney transplantation. A total of 49 patients (18.4%) had CVEs and 42 (15.8%) patients died. Being over 45 years of age and having dialysis vintage over 1 year were found to be independent risk factors for CVEs. Forty-eight out of 60 high-risk patients evaluated with noninvasive tests had negative results. Twelve out of these 48 patients had a CVE in due course. Among 10 patients who underwent coronary angiography, 1 had a CVE and 1 died. The sensitivity and specificity of the AST guidelines (area under the curve = 0.647, P = .005, sensitivity 83%, specificity 54%) were higher than Lisbon. In conclusion, the predictive risk factors for CVEs were age over 45 years and dialysis vintage over a year. Our results also suggest that exercise electrocardiography and myocardial perfusion scintigraphy for cardiac evaluation are less sensitive in CVE prediction. We recommend clinicians to use the AST guidelines and to prioritize coronary angiography in pretransplant CV assessment.

Assessment of Pulmonary Hypertension in Lung Transplantation Candidates: Correlation of Doppler Echocardiography With Right Heart Catheterization.

BACKGROUND: Right heart catheterization (RHC) remains the gold standard to diagnosis of pulmonary hypertension among lung transplantation candidates. Doppler echocardiography (DE) may be as accurate as RHC, without risks of an invasive test. The aim of the study was to assess the feasibility of DE for the measurement of pulmonary artery pressure in lung transplantation candidates and the correlation between pulmonary artery pressures estimated by DE versus measured by RHC. METHODS: A total of 103 lung transplantation candidates undergoing DE who were scheduled to undergo RHC within 72 hours were analyzed. The performance characteristics of DE were compared with RHC, and correlation analysis was performed to determine the correlation of pulmonary pressures obtained by DE versus measured by RHC. RESULTS: The prevalence of pulmonary hypertension was 57% in lung transplantation candidates. Of the 103 candidates, evaluation of pulmonary artery systolic pressure (PASP) by DE was possible in 92 (89%). Median PASP by RHC was 45 (12-145) mm Hg and by DE 45 (20-144) mm Hg. There was a positive correlation between PASP estimated by DE and measured by RHC (r = 0.585, P < .0001). Sensitivity, specificity, and positive and negative predictive values of PASP estimation for diagnosis of pulmonary hypertension were 85%, 67%, 87%, and 61%, respectively. CONCLUSIONS: There is a strong positive correlation between PASP estimated by DE compared with measured by RHC with an acceptable sensitivity and specificity in detecting pulmonary hypertension. Echocardiography can be recommended for measuring pulmonary pressures in lung transplantation candidates.

Osteoporosis in Lung Transplantation Candidates: Association With 6-minute Walking Test and Body Mass Index.

BACKGROUND: Osteoporosis is a well-recognized complication in lung transplantation because of steroid use and immobilization. The aim of the study was to assess the prevalence of osteoporosis and risk factors associated with osteoporosis in lung transplantation candidates. METHODS: The bone mineral density of 174 patients with various end-stage lung diseases was assessed at the pretransplantation period. Osteoporosis risk factors were analyzed with the consideration to principal diagnosis, demographic, and clinical parameters of lung disease, lung function tests and mobility test (6-minute walking test). A multivariate analysis was conducted to determine various demographic and clinical risk factors associated with bone mass loss in the pretransplant period. RESULTS: The prevalence of osteoporosis and osteopenia was 46% and 35%, respectively, in the study population. Osteoporotic patients have lower body mass index and lower 6-minute walking distance than patients without osteoporosis. In addition, they have higher pulmonary artery pressure and history of noninvasive mechanical ventilation than in patients without osteoporosis. There was a significant negative correlation between the 6-minute walking test, body mass index, and the presence of osteoporosis in the study population. Multivariate logistic regression analysis confirmed that 6-minute walking test (odds ratio, 0.996) and body mass index (odds ratio, 0.847) were significantly and negatively correlated with the presence of osteoporosis. CONCLUSIONS: A significant proportion of patients with end-stage lung diseases have osteopenia or osteoporosis pretransplantation. This is the first study to demonstrate that 6-minute walking distance and bone mineral density independently predict osteoporosis in lung transplant candidates.

Analysis of the Humoral Immune Response to Human Leukocyte Antigens in Turkish Renal Transplant Candidates and Relationship Between Autoimmune Disorders.

BACKGROUND: Pre-transplant sensitization to human leukocyte antigens (HLA) is a risk factor for graft failure. The purpose of the current single-center study was to evaluate humoral immune response to HLA antigens and the possible relationship between anti-HLA antibody titer and autoimmune disorders in renal transplant candidates. METHODS: A total of 435 renal transplant candidates were analyzed; 50 sensitized patients were enrolled in this study. The HLA typing was performed by use of enzyme-linked immunoassay combined with Luminex technology. The patients were questioned for clinical evidence of hypothyroidism and systemic lupus erythematosus (SLE) and investigated for anti-nuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), anti-thyroglobulin (anti-TG), anti-thyroid peroxidase (anti-TPO) antibodies, and thyroid function tests. RESULTS: Among 50 patients with positive panel reactive antibody, 24 (48%) were positive for class I and negative for class II, 12 (24%) were negative for class I and positive for class II, and 14 (28%) were positive for both classes I and II. The specificities of anti-HLA antibodies-A23, A68, A69, B27, B49, DR6, and DR8-were the most frequent. ANA and anti-dsDNA antibodies were not correlated with either clinical symptoms of SLE or anti-HLA antibody titer of renal transplant candidates. Similarly, anti-TG and anti-TPO antibodies were not correlated with clinical hypothyroidism or anti-HLA antibody titer. CONCLUSIONS: Our data have demonstrated the profile of anti-HLA antibodies in patients who were on the renal transplant waiting list in Turkey. The most frequent specificities of anti-HLA antibodies were A23, A68, A69, B27, B49, DR6, and DR8. There was no association between anti-HLA antibody titer and clinical and laboratory evidence of SLE and hypothyroidism.

Association of BK Virus Titers With Lymphocyte Count in Renal Transplant Patients.

OBJECTIVES: Regular screening for the BK virus (BKV) is recommended for early intervention in renal transplant patients. Identification of predictors for the development of BK viremia would improve their monitoring. We performed a retrospective study investigating whether the lymphocyte count may be a predictor of BKV development in renal transplant patients. PATIENTS AND METHODS: We retrospectively analyzed 268 renal transplant patients who were followed in our clinic from January 2011 to August 2014. The viral loads of BKV in blood detected by quantitative real-time polymerase chain reaction test were performed according to relevant guidelines. We also retrospectively monitored lymphocyte count, creatinine, immunosuppressive drug doses, and tacrolimus/cyclosporine/mTor inhibitors levels during the same time as BKV screening. Demographic and other clinical data were extracted from patients' files. The calculation of correlation coefficients and receiver operating characteristics (ROC) curve analysis were performed. RESULTS: Overall, 16 patients (5.9%) who experienced BKV-DNA positivity were included the study. Mean age of patients was 38.2 ± 12.8 years. All patients received steroid and calcineurin inhibitors (CNIs). Mycophenolate mofetil/mycophenolic acid (MMF/MPA) was administered to 14 patients. BKV-DNA was found in 64 of the 88 (72.7%) plasma samples. The lymphocyte count on the first day of positive BKV-DNA test was significantly lower than in those with negative BKV-DNA results (1700/µl vs 2400/µl, respectively; P = .009). Its AUC of the ROC curve was 0.77 (P = .012). The optimal cutoff point for lymphocyte count was 1900/µl, and sensitivity and specificity for predict BKV positivity were 75% and 78.57%, respectively. We also found that lymphocyte count negatively correlated with the first detectable BKV titers (r = -0.438; P = .015). However, there is no relation between CNI/mTOR inhibitor levels, MMF/MPA doses, lymphocyte count, and all BKV-titers. CONCLUSIONS: Decreased lymphocyte count may be a predictor for preceding BKV viremia. Clinicians should be more careful in terms of the decreased lymphocyte count in case of BKV replication in renal transplant patients.

Fibroblast growth factor-23 levels are associated with uric acid but not carotid intima media thickness in renal transplant recipients.

INTRODUCTION: Cardiovascular disease (CVD) is the leading cause of mortality in chronic kidney disease (CKD) patients. Fibroblast growth factor-23 (FGF-23) is associated with atherosclerosis and cardiovascular mortality in CKD patients and healthy subjects. However, data in renal transplant recipients (RTR) are scarce. We aimed to determine factors associated with FGF-23 and to explore its relationship to atherosclerosis. METHODS: Forty-six patients and 44 controls were included. FGF-23 was measured from plasma. Carotid intima media thickness (CIMT) was evaluated ultrasonographically. RESULTS: Patients had higher waist circumference (WC; 92.2 ± 14.9 vs 85.3 ± 11.0 cm; P < .05), glucose (99.8 ± 17.2 vs 90.3 ± 6.5 mg/dL; P < .01), creatinine (1.43 ± 0.6 vs 0.86 ± 0.1 mg/dL; P < .01), triglyceride (160.4 ± 58.9 vs 135.6 ± 59.8 mg/dL; P < .05), white blood cells (WBC; 7938.6 ± 2105.2 vs 6715.7 ± 1807.5 WBC/mm(3); P < .01), ferritin (217.0 ± 255.8 vs 108.3 ± 142.4 ng/mL; P < .05), uric acid (6.5 ± 1.6 vs 4.7 ± 1.3 mg/dL; P < .01), C-reactive protein (CRP; 8.2 ± 18.2 vs 5.3 ± 7.9 mg/L; P < .01), parathyroid hormone (PTH; 89.7 ± 59.2 vs 44.1 ± 16.7 pg/mL; P < .01), and alkaline phosphatase (ALP; 162.5 ± 86.6 vs 74.2 ± 21.9 U/L; P < .01). FGF-23 was higher in patients (11.7 ± 7.2 vs 9.6 ± 6.8 pg/mL; P < .05). CIMT was similar (0.58 ± 0.09 vs 0.57 ± 0.1 mm; P > .05). WC, creatinine, and uric acid were positively correlated with FGF-23, whereas albumin showed negative correlation. On multivariate analysis only creatinine and uric acid were determinants of FGF-23. CONCLUSION: FGF-23 levels are associated with uric acid in RTR. Larger studies are needed to confirm this finding.